Process for preparing star compounds

ABSTRACT

A process for preparing a three-branched or four-branched star compound comprising polymerizing an olefine compound represetned by the formula ##STR1## wherein A is a signle bond or phenylene group, and R 3  is a hydrogen atom or methyl group and R 4  is a monovalent organic group when A is a signle bond, or R 3  is a hydrogen atom and R 4  is an alkyl group when A is a phenylene group, using the adduct of a polyfunctional alkenyl ether represetned by the formula (I) 
     
         R.sup.2 --O--CH═CHR.sup.1).sub.n                       (I) 
    
     wherein R 1  is a hydrogen atom or methyl group, n is an integer of 3 or 4, and R 2  is a rtivalent organic group when n is 3 or a tetravelent organic group when n is 4 with a cation-donating compound.

FIELD OF THE INVENTION

The present invention relates to processes for preparing three-branchedor four-branched star compounds such as three-branched star polyalkenylethers, four-branched star polyalkenyl ethers, three-branched starpolyalkyloxystyrenes and four-branched star polyalkyloxystyrenes.

Such polyfunctional polyolefins are expected to be useful advancedpolymer materials as prepolymers for elastomers, crosslinking agents,ionomers, surfactants, compatibilizing agents, etc.

DESCRIPTION OF THE PRIOR ART

Alkenyl ethers and alkyloxystyrenes can be polymerized only by cationicpolymerization, whereas usual cationic polymerization involves unstablegrowing carbocation and encounters difficulties in inhibiting transferand termination reactions and therefore in forming monodisperse polymersor block copolymers with a reduced distribution of molecular weights.

However, we have found that isobutyl vinyl ether can be subjected toliving polymerization to form a polymer or block copolymer having anarrow molecular weight distribution when a binary initiator is usedwhich comprises HI, a cation-donating compound, and I₂, ZnI₂ or a metalhalide (ZnBr₂, ZnCl₂, SI₂, SCl₂, MgCl₂, BF₃ OEt₂ or SnCl₄. (SeeMacromolecules, 17, 265 (1984) for HI/I₂ initiator, Macromolecules, 20,2693 (1987) for HI/ZnI₂, and Macromolecules, 22, 1552 (1989) for metalhalides.)

As to alkyloxystyrenes, we have also found that p-methoxystyrene orp-tert-butoxystyrene can be subjected to living polymerization to give apolymer of narrow molecular weight distribution using a binary initiatorwhich comprises HI, a cation-donating compound, and ZnI₂ (PolymerBulletin, 1988, 19, 7-11, and Macrool. Chem., Suppl., 1989, 15, 127136).

Three- or four-branched star polymers are advanced polymers which havethree or four branched chains extending radially from a common centerand three or four active ends. Accordingly, they possess such physicalproperties that are not available with conventional linear highpolymers, can be used for wider application, for example, as prepolymersfor elastomers, crosslinking agents, ionomers, surfactants,compatibilizing agents, etc. and are expected to be useful advancedpolymer materials.

However, the initiator for use in the living cationic polymerization ofalkenyl ethers is the adduct of a monofunctional alkenyl ether with acation-donating compound. Since this adduct forms only one active siteper molecule, it has been impossible to prepare star polymers.

SUMMARY OF THE INVENTION

In view of the above situation, the main object of the present inventionis to provide a process for preparing a three- or four-branched starcompound.

To fulfill this object, the present invention provides a process forpreparing a three-branched or four-branched star compound represented bythe formula ##STR2## wherein A is a single bond or phenylene group, n isan integer of 3 or 4, R¹ is a hydrogen atom or methyl group, R² is atrivalent organic group when n is 3 or a tetravalent organic group whenn is 4, R³ is a hydrogen atom or methyl group when A is a single bond ora hydrogen atom when A is a phenylene group, R⁴ is a monovalent organicgroup when A is a single bond or an alkyl group when A is a phenylenegroup, x is 1 to 10000 and Z is a terminator residue, the processcomprising polymerizing an olefin compound represented by the formula##STR3## wherein A, R³ and R⁴ are as defined above, using as aninitiator the adduct of a polyfunctional alkenyl ether represented bythe formula

    R.sup.2 --O--CH═CHR.sup.1).sub.n                       (I)

wherein R¹, R² and n are as defined above with a cation-donatingcompound.

The process of the invention will be described first for the preparationof three-branched star compounds.

According to the present process, an alkenyl ether represented by theformula ##STR4## wherein R³ is a hydrogen atom or methyl group, and R⁴is a monovalent organic group is polymerized using as the initiator theadduct of a trifunctional alkenyl ether represented by the formula##STR5## wherein R¹ is a hydrogen atom or methyl group, and R² is atrivalent organic group with a cation-donating compound to prepare athree-branched star alkenyl ether represented by the formula ##STR6##wherein x is 1 to 10,000, Z is a terminator residue, and R¹, R², R³ andR⁴ are as defined above.

Further according to the present process, an alkyloxystyrene representedby the formula ##STR7## wherein A is a phenylene group, and R⁴ is analkyl group is polymerized using the adduct of a trifunctional alkenylether represented by the formula (Ia) with a cation-donating compound asthe initiator, and a bivalent metal halide as an activating agent toprepare a corresponding three-branched star alkyloxystyrene representedby the formula ##STR8## wherein x is 1 to 10,000, Z is a terminatorresidue, and R¹, R², R⁴ and A are as defined above.

Next, the process of the invention will be described for the preparationof four-branched star compounds.

According to the process of the invention, an alkenyl ether representedby the formula ##STR9## wherein R³ is a hydrogen atom or methyl group,and R⁴ is a monovalent organic group is polymerized using as theinitiator the adduct of a tetrafunctional alkenyl ether represented bythe formula ##STR10## wherein R¹ is a hydrogen atom or methyl group, andR² is a tetravalent organic group with a cation-donating compound toprepare a four-branched star alkenyl ether represented by the formula##STR11## wherein x is 1 to 10,000, Z is a terminator residue, and R¹,R², R³ and R⁴ are as defined above.

Further according to the present process, an alkyloxystyrene representedby the formula ##STR12## wherein A is a phenylene group, and R⁴ is analkyl group is polymerized using the adduct of a tetrafunctional alkenylether represented by the formula (Ib) with a cation-donating compound asthe initiator, and a bivalent metal halide as an activating agent toprepare a corresponding four-branched star alkyloxystyrene representedby the formula ##STR13## wherein x is 1 to 10,000, Z is a terminatorresidue, and R¹, R², R⁴ and A are as defined above.

DETAILED DESCRIPTION OF THE INVENTION

Given in Tables 1 to 6 are examples of trifunctional alkenyl ethers (Ia)for use in preparing three-branched star compounds.

    ______________________________________                                        trifunctional                                                                 alkenyl ether                                                                            R.sup.2                                                            ______________________________________                                        R.sup.1 ; hydrogen atom (H)                                                   trivinyloxyethyl 1,3,5-benzene- tricarboxylate                                            ##STR14##                                                         trivinyloxyethyl 1,2,3-benzene- tricarboxylate                                            ##STR15##                                                         trivenyloxyethyl 1,3,4-benzene- tricarboxylate                                            ##STR16##                                                         1,3,5-tri- vinyloxyethyl benzene                                                          ##STR17##                                                         1,2,3-tri- vinyloxyethoxy benzene                                                         ##STR18##                                                         1,3,4,-tri- vinyloxyethoxy benzene                                                        ##STR19##                                                         1,1,1-tris(4- vinyloxyethoxy carbonylphenyl) ethane                                       ##STR20##                                                         1,1,1-tris(4- vinyloxyethoxy phenyl)ethane                                                ##STR21##                                                         1,1,2-tris(4- vinyloxyethoxy carbonylphenyl) ethane                                       ##STR22##                                                         1,1,2-tris(4- vinyloxyethoxy- phenyl)ethane                                               ##STR23##                                                         1,1,1-tris(4- vinyloxyethoxy- carbonylmethyl) ethane                                      ##STR24##                                                         1,1,1-tris(4- vinyloxyethoxy- methyl)ethane                                               ##STR25##                                                         1,1,2-tris(4- vinyloxyethoxy- carbonylmethyl) ethane                                      ##STR26##                                                         1,1,2-tris(4- vinyloxyethoxy- methyl)ethane                                               ##STR27##                                                         R.sup.1 ; methyl (CH.sub.3)                                                   tripropenyloxy- ethyl 1,3,5- benzenetri- carboxylate                                      ##STR28##                                                         tripropenyloxy- ethyl 1,2,3- benzenetri- carboxylate                                      ##STR29##                                                         tripropenyloxy- ethyl 1,3,4- benzenetri- carboxylate                                      ##STR30##                                                         1,3,5-tri- propenyloxy- ethoxybenzene                                                     ##STR31##                                                         1,2,3-tri- propenyloxy- ethoxybenzene                                                     ##STR32##                                                         1,3,4-tri- propenyloxy- ethoxybanzene                                                     ##STR33##                                                         1,1,1-tris(4- propenyloxy- ethoxycarbonyl- phenyl)ethane                                  ##STR34##                                                         1,1,1-tris(4- propenyloxy- ethoxyphenyl) ethane                                           ##STR35##                                                         1,1,2-tris(4- propenyloxy- ethoxycarbonyl- phenyl)ethane                                  ##STR36##                                                         1,1,1-tris(4- propenyloxy- ethoxycarbonyl- phenyl)ethane                                  ##STR37##                                                         1,1,2-tris(4- propenyloxy- ethoxyphenyl) ethane                                           ##STR38##                                                         1,1,1-tris(4- propenyloxy- ethoxymethyl) ethane                                           ##STR39##                                                         1,1,2-tris(4- propenyloxy- ethoxycarbonyl- methyl)ethane                                  ##STR40##                                                         1,1,2-tris(4- propenyloxy- ethoxymethyl) ethane                                           ##STR41##                                                         ______________________________________                                    

Among the trifunctional alkenyl ethers (Ia), those wherein the group R²has an ether linkage are prepared, for example, by reacting acorresponding trifunctional alcohol with 2-chloroethyl vinyl ether or2-chloroethyl propenyl ether in dimethyl sulfoxide in the presence ofsodium hydroxide.

Among the trifunctional alkenyl ethers (Ia), those wherein the group R²has an ester linkage are prepared, for example, by converting2-hydroxyethyl vinyl ether or 2-hydroxyethyl propenyl ether to a sodiumsalt with sodium hydride in toluene, and reacting the salt with acorresponding trifunctional carboxyic acid chloride.

The tetrafunctional alkenyl ethers (Ib'), (Ib") for use in preparingfour-branched polymers have the following respective structures.##STR42## wherein R¹ is a hydrogen atom or methyl group.

Examples of tetrafunctional alkenyl ethers (Ib') are as follows.

1,1,4,4-Tetrakis[4-(2-vinyloxy)ethoxyphenyl]cyclohexane,

1,1,4,4-Tetrakis[4-(2-propenyloxy)ethoxyphenyl]cyclohexane.

Examples of tetrafunctional alkenyl ethers (Ib") are as follows.

1,1,3,3-Tetrakis[4-(2-vinyloxy)ethoxyphenylcyclohexane,

1,1,3,3-Tetrakis[4-(2-propenyloxy)ethoxyphenyl]cyclohexane.

The tetrafunctional alkenyl ether (Ib') or (Ib") is prepared, forexample, by reacting tetrakis(4-hydroxyphenyl)cyclohexane withchloroethyl vinyl ether oroethyl propenyl ether in dimethyl sulfoxide inthe presence of sodium hydroxide.

Examples of cation-donating compounds for use in the process of theinvention are CF₃ COOH, CCl₃ COOH, CH₃ COOH, HCOOH, H₃ PO₄, HOPO(OC₄H₇)₂, HOPO(OC₆ H₅)₂, HOPO(C₆ H₅)₂, HI, HCl, HBr, etc.

The process of the present invention employs as an initiator the adductof a polyfunctional alkenyl ether (I) with a cation-donating compound,i.e., the adduct of a trifunctional alkenyl ether (Ia) with acation-donating compound, or the adduct of a tetrafunctional alkenylether (Ib') or (Ib") with a cation-donating compound. When thecation-donating compound is represented by HB, the adduct is representedby

    R.sup.2 --O--CHB--CH.sub.2 R.sup.1).sub.n                  (IV)

wherein R¹, R² and n has the same meaning as above, and B is the portionof the compound remaining after the donation of cation.

Generally, the adduct (IV) is prepared, for example, by dissolving apolyfunctional alkenyl ether (I) in an inert solvent (preferably of thesame kind as the solvent to be used for the polymerization reaction),such as carbon tetrachloride, n-hexane or toluene, under dry nitrogen atroom temperature, and adding an equivalent amount of the cation-donatingcompound HB to the solution for reaction. The molar ratio of thetrifunctional alkenyl ether (Ia) to the cation-donating compound HB tobe added thereto is substantially 1:3. The molar ratio of thetetrafunctional alkenyl ether (Ib'), (Ib") to the cation-donatingcompound is substantially 1:4. The reaction is conducted at a suitabletemperature usually in the range of -90° C. to 100° C., generally atatmospheric pressure although an increased pressure is applicable. Thereaction time is 10 seconds to 24 hours, preferably 5 minutes to 1 hour.The reaction of this method proceeds rapidly, quantitatively giving asolution of the adduct (IV). Although the adduct (IV) may be isolatedfrom the solution, the solution can be used as it is for thepolymerization without isolation.

The polymerization degree of the polymer is dependent on the molar ratio(100% polymerization ratio) of the olefin compound (II) to the adduct(IV), so that the amount of adduct (IV) is critical. The molar ratio ofthe olefin compound (II) to the adduct (IV) is determined according tothe desired polymerization degree, whereby the polymer can be given thedesired molecular weight. The molar ratio is at least 3 when thethree-branched star compound is to be obtained, or at least 4 when thefour-branched star compound is to be obtained. Thus, the molar ratio issuitably determined according to the desired polymerization degree.

Among the alkenyl ethers represented by the formula (IIa) and includedin olefin compounds (II) which are monomers for use in the invention forpolymerization, those wherein R⁴ is a monovalent organic group are, forexample, as follows.

Methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl,tert-butyl, n-pentyl, isopentyl, 1,2-dimethylpropyl, n-hexyl, isohexyl,2-ethylbutyl, 1,3-dimethylbutyl, n-heptyl, isoheptyl, n-octyl,1-methylheptyl, 2-ethylhexyl, n-nonyl, 2-methyloctyl, n-decyl,1-pentylhexyl, 4-ethyl-1-methyloctyl, n-dodecyl, n-tetradecyl,n-hexadecyl, n-octadecyl, n-eicosyl, n-docosyl and like alkyl groups;cyclohexyl and like cycloalkyl groups; cyclohexylmethyl, terpenyl,menthyl, bornyl, isobornyl and like cycloalkylalkyl groups; benzyl,p-methylbenzyl, p-chlorobenzyl, p-phenylbenzyl, 1-phenylethyl,2-phenylethyl, 2-phenylpropyl, 3-phenylpropyl, 1,1-dimethylbenzyl,benzhydryl, 3-phenylpropane-2-yl and like aralkyl groups; cinnamyl,1-methylcinnamyl, 3-methylcinnamyl, 3-phenylcinnamyl, 2-phenylallyl,1-methyl-2-phenylally and like arylalkenyl groups; phenyl, o-tolyl,m-tolyl, p-tolyl, p-tert-butylphenyl, mesityl, p-isohexylphenyl,p-isooctylphenyl, o-chlorophenyl, m-chlorophenyl, p-chlorophenyl,o-bromophenyl, m-bromophenyl, p-bromophenyl, o-methoxyphenyl,m-methoxyphenyl, p-methoxyphenyl, o-nitrophenyl, m-nitrophenyl,p-nitrophenyl, 2,4-dinitrophenyl and like aryl groups; 1-chloroethyl,2-chloroethyl, 2-bromoethyl, 2-iodoethyl, 2-fluoroethyl,2,2,2-trifluoroethyl, 3-chloropropyl and like haloalkyl groups;methoxyethyl, ethoxyethyl, 2-ethoxyethoxyethyl and like alkoxyalkylgroups, and phenoxyethyl, p-chlorophenoxyethyl, p-bromophenoxyethyl,p-fluorophenoxyethyl, p-methoxyphenoxyethyl and like aryloxyalkylgroups; 2-acetoxyethyl, 2-benzoxyethyl, 2-(p-methoxybenzoxy)ethyl,2-(p-chlorobenzoxy)ethyl and like acryloxyalkyl groups;2-phthaliminoethyl, 2-(di-tert-butylcarboxyimino)ethyl and likeiminoalkyl groups; 2-diethylmalonylethyl, 2-diphenylmalonylethyl andlike malonylalkyl groups; 2-acryloxyethyl, 2-methacryloxyethyl,2-cinnamyloxyethyl, 2-sorbinyloxy and like aryloxyalkyl groups; etc.

Such olefins (IIa) may be used singly, or at least two of them may beused in combination.

The process wherein the olefin (IIa) is used is practiced preferably byemploying a method of accelerating the polymerization (livingpolymerization). There are the following two methods for this purpose.

The first of these methods is a method wherein the living polymerizationis conducted in the presence of an organoaluminum compound as acatalyst, with the growing carbocation protected with a Lewis base tothereby prevent a side reaction. In the second method, the livingpolymerization is conducted, with a Lewis acid used for adjusting thenucleophilic property of the counteranion for the growing carbocation toprevent a side reaction.

These methods will be described below in greater detail.

With the first method, an organoaluminum compound represented by thefollowing formula (V) is used as a catalyst in the presence of a Lewisbase.

    R.sup.5.sub.r ΛIX.sub.s                             (V)

wherein R⁵ is a monovalent organic group, X is a halogen atom, and r ands are each an integer and are in the relation defined by r+s=3, 0≦r<3and 0 ≦s<3.

Examples of useful organoaluminum compounds (V) are trichloro-aluminum,tribromo-aluminum, ethylaluminum dichloride, ethylaluminum dibromide,diethylaluminum chloride, diethylaluminum bromide, ethylaluminumdiiodide, ethylaluminum difluoride, methylaluminum dichloride,methylaluminum dibromide, dimethylaluminum chloride, dimethylaluminumbromide and the like. These organoaluminum compounds may be used singly,or at least two of them may be used in combination. The compound is usedin such an amount that the molar ratio of the olefin (II) to theorganoaluminum compound (V) is generally in the range of 2 to 10,000,preferably in the range of 10 to 5000.

Examples of useful Lewis bases to be present in the reaction system areethyl acetate, n-butyl acetate, phenyl acetate, ethyl benzoate, ethylp-chlorobenzoate, ethyl p-methylbenzoate, ethyl p-methoxybenzoate,methyl acetate, isopropyl acetate, tert-butyl acetate and like estercompounds; 1,4-dioxane, diethyl ether, tetrahydrofuran, di-n-hexylether, diisopropyl ether, di-n-butyl ether, methoxytoluene, propyleneoxide, 1,2-diethoxyethane, 1,2-dibutoxyethane, diethylene glycoldimethyl ether, diethylene glycol diethyl ether, diethylene glycoldibutyl ether, acetal and like ether compounds; pyridine,2,6-dimethylpyridine, 2-methylpyridine, 2,4,6-trimethylpyridine,2,4-dimethylpyridine, 2,6-di-tert-butylpyridine and like pyridinederivatives.

These Lewis bases are usably singly, or at least two of them can be usedin combination. The base is usable in bulk or as dissolved in an inertsolvent. In accordance with the basicity of the Lewis base, the Lewisbase is added to the reaction system in such an amount that the ratio ofthe amount to the amount of alkenyl ether (I) used is in the followingrange. ##EQU1##

The ratio of the amount of Lewis base used to the amount of alkenylether (I) used, if less than 0.001 or over 100, is not desirable sinceit is then difficult to provide a perfect living polymerization system.

The second method employs a Lewis acid for suitably activating thecounteranion for the growing carbocation. Examples of useful Lewis acidsare iodine, zinc(II) halides, tin(II) halides, etc., among which I₂,ZnI₂, ZnBr₂, ZnCl₂, SnI₂ and SnCl₂ are especially suitable to use. SuchLewis acids are used singly, or at least two of them are used incombination. The Lewis acid is used in such an amount that the molarratio of the alkenyl ether (I) to the acid is usually in the range of 2to 100,000, preferably in the range of 10 to 10,000.

Examples of alkyloxystyrenes represented by the formula (IIb) andincluded in the olefin compounds (II) for use in the process of theinvention are o-methoxystyrene, m-methoxystyrene, p-methoxystyrene,o-ethoxystyrene, m-ethoxystyrene, p-ethoxystyrene, o-n-propyloxystyrene,m-n-propyloxystyrene, p-n-propyloxystyrene, o-isopropyloxystyrene,m-isopropyloxystyrene, p-isopropyloxystyrene, o-n-butoxystyrene,m-n-butoxystyrene, p-n-butoxystyrene, o-tert-butoxystyrene,m-tert-butyoxystyrene, p-tert-butoxystyrene and the like. These styrenesmay be used singly or in combination.

In the process wherein the alkyloxystyrene (IIb) is used, thepolymerization (living polymerization) is effected using a halide of abivalent metal as an activating agent.

The metal halide serves to activate the counteranion for the growingcarbocation during the polymerization. Examples of useful metal halidesare ZnI₂, ZnBr₂, ZnCl₂, SnI₂, SnCl₂ and the like.

Such metal halides are used singly, or at least two of them are used incombination. The metal halide is used in such an amount that the molarratio of the polyfunctional alkenyl ether (I) to the metal halide is inthe range of 0.01 to 1000, preferably 0.1 to 100.

The polymerization reaction of the present invention is carried outusually by solution polymerization, while other methods, such as bulkpolymerization, can also be used. Examples of solvents useful forsolution polymerization are n-hexane, cyclohexane, benzene, toluene,carbon tetrachloride, ethylene chloride and like inert solvents. Thereaction is conducted at a suitable temperature usually within the rangeof -40° C. to 100° C., generally at atmospheric pressure although anincreased pressure is applicable. The reaction time is 3 seconds to 7days, preferably 1 minute to 24 hours.

Since the polymerization reaction of the present invention is livingpolymerization, the polymerization reaction is terminated by adding apolymerization terminator. The polymerization terminator is preferably acompound represented by HZ (wherein Z is the terminator residue), suchas methanol, ethanol, propanol, isopropanol, butanol or like alcohol; ordimethylamine, diethylamine or like amine. When methanol is used, it isdesirable to use ammonia water in combination therewith. Ammonia acts todeactivate the organoaluminum compound (V), Lewis acid and metal halide.The molar ratio of the polymerization terminator to the cation-donatingcompound HB is 1 to 10,000, preferably 1 to 1000.

The polymer formed is collected by washing the reaction mixture with anaqueous solution of hydrochloric acid or like acid and then with water,and removing the solvent from the mixture.

The reaction product of the present invention, i.e., star compound, hasa polymerization degree x in the range of 1 to 10,000, preferably 4 to5000, more preferably 10 to 1000, most preferably 10 to 600.

The process of the present invention provides star compounds havingthree or four branches of uniform length and having a narrow molecularweight distribution. Furthermore, the star compounds prepared by thepresent process have active polymer ends. This makes it possible, forexample, to prepare block copolymers from the present polymer and otherpolymer, or to introduce a functional group into the present polymer atthe terminal position. Depending on the kind of monomer used, thepolymer can be made hydrophilic by a reaction of the polymer.Furthermore, a block copolymer can be prepared which compriseshydrophilic blocks and hydrophobic blocks. Thus, the star polymers ofthe invention are usable for wider application as functional polymersand are expected to find use in prepolymers for novel elastomers,crosslinking agents, ionomers, surfactants, compatibilizing agents, etc.

EXAMPLES

The present invention will be further described with reference to thefollowing examples, in which the molar concentration (mole /1) indicatesthe amount in moles of the compound used based on the whole volume ofthe polymerization system, the weight average molecular weight isrepresented by Mw, and the number average molecular weight by Mn. TheMw, Mn and the ratio Mw/Mn were determined by light diffusion gelpermeation chromatography GPC ("LS8000 System," product of Toyo SodaMfg. Co., Ltd., column: "Polystyrene Gel KF-802, KF-803, KF-804,"product of Showa Denko K.K., 8 mm in inside diameter, 300 mm in length).The chemical structure of the polymer was determined by ¹ H-NMR("GSX-270," product of JEOL, Ltd., 270 MHz). The adducts used inExamples of a polyfunctional alkenyl ether (I) with a cation-donatingcompound were prepared by dissolving the ether (I) in a fully purifiedand dried inert solvent (of the same kind as the solvent used forpolymerization reaction), adding an equivalent amount of cation-donatingcompound HB to the solution and stirring the mixture at room temperaturein a nitrogen stream for 15 minutes. The adduct obtained was used forpolymerization in the form of a solution without isolation.

REFERENCE EXAMPLE 1 Preparation of trifunctional alkenyl ether

A 9.96 g quantity (113 mmoles) of 2-hydroxyethyl vinyl ether wasdissolved in 50 ml of toluene in a nitrogen atmosphere withinthree-necked glass flask equipped with a condenser and a stirrer, 2.71 g(113 mmoles) of sodium hydride powder was added to the solution, and themixture was stirred at room temperature for 1 hour. To the solution werethen added 10.0 g (33.7 mmoles) of trimesic acid chloride and 0.5 g oftetra-n-butylammonium chloride, followed by reaction at 80° C. for 4hours. The reaction mixture was subjected to extraction with diethylether, and the extract was dried to give crude crystals, which were thenrecrystallized from toluene/hexane (1:1), affording tri(2-vinyloxy)ethyl1,3,5-benzenetricarboxylate (the first compound in Table 1). Yield: 62%,m.p.: 92°-93° C. (pale yellow crystals), IR absorption spectrum (Nujol):ν_(C=C) =1620 cm⁻¹, ν_(Ph) =830 cm³¹ 1.

REFERENCE EXAMPLE 2 Preparation of trifunctional alkenyl ether

A 10.0 g quantity (32.6 mmoles) of 1,1,1-tris(4-hydroxyphenyl ethane wasdissolved in 75 ml of dimethyl sulfoxide in dry nitrogen within athree-necked glass flask equipped with a condenser and a stirrer, 23.5 g(587 mmoles) of sodium hydroxide powder was added to the solution, andthe mixture was stirred at 75° C. for 3 hours. To the solution was thenadded 59.7 ml (587 mmoles) of 2-chloroethyl vinyl ether, and the mixturewas reacted at 80° C. for 5 hours. The reaction mixture was purified inthe same manner as in Reference Example ]to obtain1,1,1-tris[4-(2-vinyloxyl)ethoxylphenyl]ethane (the second compound inTable 2).

REFERENCE EXAMPLE 3 Preparation of tetrafunctional alkenyl ether

A 10.0 g quantity (22.1 mmoles) of1,1,4,4-tetrakis(4-hydroxyphenyl)cyclohexane was dissolved in 75 ml ofdimethyl sulfoxide in a nitrogen stream within a three-necked glassflask equipped with a condenser and a stirrer, 21.2 g (530 mmoles) ofsodium hydroxide powder was added to the solution, and the mixture wasstirred at 75° C. for 3 hours. Subsequently, 53.9 ml (530 mmoles) of2-chloroethyl vinyl ether was added to the solution and reactedtherewith at 80° C. for 5 hours. The reaction mixture was purified inthe same manner as in Reference Example I, giving1,1,4,4-tetrakis[4-(2vinyloxy)ethoxypheny]cyclohexane. Yield: 48%, m.p.:137.5°-139° C. (pale yellow crystals), IR absorption spectrum (Nujol):ν_(C=C) =1620 cm⁻¹, ν_(Ph) 830 cm⁻¹.

REFERENCE EXAMPLE 4 Preparation of tetrafunctional alkenyl ether

1,1,4,4-Tetrakis4-(2-propenyloxy)ethoxyphenyl]cyclohexane was preparedin the same manner as in Reference Example 3 with the exception of using63.9 ml (530 mmoles) of 2-chloroethyl propenyl ether in place of2-chloroethyl vinyl ether.

REFERENCE EXAMPLE 5 Preparation of tetrafunctional alkenyl ether

1,1,3,3-Tetrakis[4-(2-vinyloxy)ethoxyphenyl]cyclohexane was prepared inthe same manner as in Reference Example 3 with the exception of using10.0 g (22.1 mmoles) of 1,1,3,3-tetrakis(4-hydroxyphenyl)cyclohexaneinstead of 1,1,4,4-tetrakis(4-hydroxyphenyl)cyclohexane.

EXAMPLE 1

A 2.0 ml quantity (3.0 moles/1) of isobutyl vinyl ether was dissolved in1.5 ml of n-hexane fully purified and dried in a nitrogen atmosphere.With addition of 0.5 ml (1.2 moles/1) of 1,4-dioxane, the solution wasmaintained at a temperature of 0° C. To the solution were added first0.5 ml (1.7 mmoles/1) of the adduct of1,1,1-tris[4-(2-vinyloxy)ethoxyphenyl]ethane (the second compound inTable 2) with trifluoroacetic acid (CF₃ COOH), as diluted with n-hexane,and then 0.5 ml (1.7 mmoles/1) of hexane solution of ethylaluminumdichloride to initiate polymerization, which was continued at 0° C. for3 hours. Methanol (170 mmoles/1) containing a small amount of ammoniawater was thereafter added to the reaction system to terminate thepolymerization. The reaction mixture was washed with an aqueous solutionof hydrochloric acid (8 vol. %) first and then with water, followed bythe removal of the catalyst residue and then by the removal of thesolvent, etc. by evaporation to collect a polymer.

The above procedure gave a three-branched star polyisobutyl vinyl etherwhich was 1.6×10⁵ in Mn and 1.04 in Mw/Mn. The Mn value was in goodagreement with the value of 1.8×10⁵ which was calculated on theassumption that one molecule of the adduct formed a three-branchedmolecule. Values Obtained by ¹ H-NMR Spectroscopy (270 MHz, CDCl₃)

    ______________________________________                                        (Trifunctional vinyl ether)                                                    ##STR43##                                                                    δ(ppm): Peaks                                                                       a        2.05(s, 3H, CH.sub.3)                                                d        4.00(t, 6H, CH.sub.2)                                                e        4.15(t, 6H, CH.sub.2)                                                g        4.00 and 4.25(dd, 6H, CH.sub.2)                                      f        6.50(dd, 3H, CH)                                                     b        6.80(d, 6H, aromatic)                                                c        7.00(d, 6H, aromatic)                                    (Trifunctional initiator)                                                      ##STR44##                                                                    δ(ppm): Peaks                                                                       g        1.50(s, 9H, CH.sub.3)                                                a        2.05(s, 3H, CH.sub.3)                                                d + e    4.00(m, 12H, CH.sub.2)                                               f        6.15(q, 3H, CH)                                                      b        6.70(d, 6H, aromatic)                                                c        6.90(d, 6H, aromatic)                                    (Three-branched polyvinyl ether)                                               ##STR45##                                                                    δ(ppm): Peaks                                                                       k        0.90(18xH, CH.sub.3)                                                 f        1.20(9H, CH.sub.3)                                                   g + j    1.40-2.00(9xH, CH.sub.2)                                             a        2.10(3H, CH.sub.3)                                                   d,e,h,i,n                                                                              3.00-4.00                                                            c        4.10(6H, CH.sub.2)                                                   m        4.65(3H, CH)                                                         b        6.75-7.00(12H, aromatic)                                 ______________________________________                                    

EXAMPLE 2

A 1.0 ml quantity (1.5 moles/1) of isobutyl vinyl ether was dissolved in2.5 ml of n-hexane fully purified and dried in a nitrogen atmosphere.With addition of 0.5 ml (1.2 moles/1) of 1,4-dioxane, the solution wasmaintained at a temperature of 0° C. To the solution were added first0.5 ml (3.5 mmoles/1) of the adduct of tri(2-vinyloxy)ethyl1,3,5-benzenetricarboxylate (the first compound in Table 1) withtrifluoroacetic acid, as diluted with n-hexane, and then 0.5 ml (10mmoles/1) of hexane solution of ethylaluminum dichloride to initiatepolymerization. The same procedure as in Example 1 was thereafterfollowed to obtain a polymer.

The above process afforded a three-branched star polyisobutyl vinylether which was 3.8×10⁴ in Mn and 1.12 in Mw/Mn. The Mn value was ingood agreement with the value of 3.9×10⁴ which was calculated assumingthat one molecule of the adduct formed a three-branched molecule.

Further to substantiate that the three-branched star polyisobutyl vinylether was a polymer having branches of uniform length, the three esterlinkages in the organic group R² in the center of the star polymer werehydrolyzed by immersing the polymer in an aqueous solution of sodiumhydroxide at room temperature for 2 days with stirring. The branchedpolymer obtained was 1.3×10⁴ in Mn and 1.06 in Mw/Mn. This indicatedthat the three-branched star polyisobutyl vinyl ether was a polymerhaving three branches of uniform length.

EXAMPLE 3

A 1.0 ml quantity (0.38 mole/1) of toluene solution of methyl vinylether was added to 2.50 ml of toluene fully purified and dried in anitrogen atmosphere. To the solution was then added 0.5 ml (1.2 moles/1)of 1,4-dioxane. Further added to the solution were 0.5 ml (3.5 mmoles/1)of the same adduct as used in Example 1, and 0.5 ml (10 mmoles/1) ofhexane solution of ethylaluminum dichloride to initiate polymerizationat -15° C. The polymerization was continued for 3 hours, followed by thesame procedure as in Example 1 to obtain a polymer.

Consequently, a hydrophilic three-branched star polymethyl vinyl etherwas prepared which was 6.7×10³ in Mn and 1.05 in Mw/Mn. The Mn valueagreed well with the value of 6.9×10³ which was calculated assuming thatone molecule of the adduct formed a three-branched molecule.

EXAMPLE 4

A polymer was prepared by the same procedure as in Example 1 except thatthe polymerization was conducted at a temperature of 60° C. for 10minutes.

The polymer obtained was a three-branched star polyisobutyl vinyl etherwhich was 1.5×10⁵ in Mn and 1.10 in Mw/Mn. The Mn value agreed well withthe value of 1.8×10⁵ which was calculated assuming that one molecule ofthe adduct formed a three-branched molecule.

EXAMPLE 5

A 0.25 ml quantity (0.35 mole/1) of isobutyl vinyl ether was dissolvedin 3.25 ml of n-hexane fully purified and dried in a nitrogenatmosphere. A 0.5 ml quantity (1.2 moles/1) of 1,4-dioxane was added tothe solution. Further added to the solution were 0.5 ml (3.5 mmoles/1)of the same adduct as used in Example 1 and 0.5 ml (10 mmoles/1) ofhexane solution of ethylaluminum dichloride to initiate polymerizationat 0° C. Three minutes after the start of the reaction, 0.25 ml (0.38mole/1) of 2-vinyloxyethyl acetate was added to the mixture, followed byfurther polymerization at a temperature of 40° C. for 3 hours. The sameprocedure as in Example 1 was thereafter repeated to obtain a polymer.

The polymer was a three-branched star block copolymer which was 2.8×10⁴in Mn and 1.04 in Mw/Mn. The Mn value agreed well with the value of2.6×10⁴ which was calculated assuming that one molecule of the adductformed a three-branched molecule.

The polymer was further hydrolyzed with an alkali to convert thepoly-2-acetoxyethyl vinyl ether on the outer side to poly-2-hydroxyethylvinyl ether and obtain an amphiphatic three-branched star polymer havinghydrophobic groups internally and hydrophilic groups externally.

EXAMPLE 6

The procedure of Example 5 was repeated with the exception of using 0.25ml (0.38 mole/1) of 2-vinyloxyethyl acetate first in place of isobutylvinyl ether to effect polymerization at 40° C. for 2 hours, followed byaddition of 0.25 ml (0.38 mole/1) of isobutyl vinyl ether to effectfurther polymerization at 40° C. for 1 hour.

As a result, a three-branched star block copolymer was obtained whichwas 2.3×10⁴ in Mn and 1.11 in Mw/Mn. The Mn value agreed well with thevalue of 2.6×10⁴ which was calculated assuming that one molecule of theadduct formed a three-branched molecule.

The polymer was further hydrolyzed with an alkali to convert thepoly-2-acetoxyethyl vinyl ether on the inner side to poly-2-hydroxyethylvinyl ether and prepare an amphiphatic three-branched star polymerhaving hydrophilic groups internally and hydrophobic groups externally.

EXAMPLE 7

A 0.5 ml quantity (0.76 mole/1) of isobutyl vinyl ether was dissolved in3.5 ml of toluene fully purified and dried in a nitrogen atmosphere, andthe solution was maintained at a temperature of -15° C. To the solutionwere added first 0.5 ml (3.0 mmoles/1) of the adduct of1,1,1-tris[4-(2-vinyloxy)ethoxyphenyl]ethane (the second compound inTable 2) with hydrogen iodide, as diluted with toluene, and then anethereal solution (0.2 mmole/1) of zinc iodide (ZnI₂) to effectpolymerization at -15° C. for 1 hour. Methanol (300 mmoles/1) containinga small amount of ammonia was then added to the reaction system toterminate the polymerization. The reaction mixture was washed with asodium thiosulfate aqueous solution (8 vol. %) first then with water,followed by the removal of the catalyst residue and thereafter by theremoval of the solvent, etc. by evaporation to obtain a product.

The product obtained was a three-branched star polyisobutyl vinyl etherwhich was 2.8×10⁴ in Mn and 1.04 in Mw/Mn. The Mn value agreed well withthe valuce of 2.6×10⁴ which was calculated assuming that one molecule ofthe adduct formed a three-branched molecule.

EXAMPLE 8

The same procedure as in Example 7 was repeated with the exception ofusing the adduct (3.0 mmoles/1) of tri(2-vinyloxy)ethyl1,3,5-benzenetricarboxylate (the first compound in Table 1) withhydrogen iodide, as diluted with toluene, in place of the adduct used inExample 7. Consequently, a three-branched star polyisobutyl vinyl etherwas obtained which was 3.3×10⁴ in Mn and 1.04 in Mw/Mn.

EXAMPLE 9

A 0.25 ml quantity (0.38 mole/1) of 2-vinyloxyethyl acetate wasdissolved in 3.0 ml of toluene fully purified and dried in a nitrogenatmosphere, and the solution was maintained at a temperature of -15° C.To the solution were added first 0.5 ml (3.0 mmoles/1) of the sameadduct as used in Example 5, and then a toluene solution (9.0 mmoles/1)of iodine (I₂) to start polymerization. After continuing thepolymerization at -15° C. for 1 hour, the same procedure as in Example 5was repeated to prepare a polymer.

The polymer obtained was a three-branched star poly-2-acetoxyethy vinylether which was 1.9×10⁴ in Mn and 1.08 in Mw/Mn. The Mn value agreedwell with the value of 1.7×10⁴ which was calculated assuming that onemolecule of the adduct formed a three-branched molecule.

EXAMPLE 10

A 0.25 ml quantity (0.38 mole/1) of p-methoxystyrene was dissolved in3.75 ml of toluene fully purified and dried in a nitrogen atmosphere,and the solution was maintained at a temperature of -78° C. To thesolution were added first 0.5 ml (3.3 mmoles/1) of the adduct of1,1,1-tris[4-(2-vinyloxy)ethoxyphenyl]ethane (the second compound inTable 2) with hydrogen iodide, as diluted with toluene, and then 0.5 ml(3.3 mmoles/1) of ethereal solution of zinc iodide. The resultingsolution was allowed to stand at -78° C. for 20 hours and thereafterheated to -15° C. to start polymerization. After continuing thepolymerization at -15° C. for 2 hours, methanol (330 mmoles/1)containing a small amount of ammonia water was added to the reactionsystem to terminate the polymerization and obtain a mixture containing apolymer. The mixture was washed first with hydrochloric acid aqueoussolution (8 vol. and then with water, and the solvent, etc. wereevaporated off the mixture to collect the polymer.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was athree-branched star poly(p-methoxystyrene) which was 1.4×10⁴ in Mn and1.05 in Mw/Mn. The Mn value agreed well with the value of 1.5×10⁴ whichwas calculated assuming that one molecule of the adduct formed athree-branched molecule. Values Obtained by ¹ H-NMR Spectroscopy (270MHz, CDCl₃)

    ______________________________________                                        (Three-branched poly(p-methoxystyrene))                                        ##STR46##                                                                    δ(ppm): Peaks                                                                       f        0.90(9H, CH.sub.3)                                                   g + h    1.20-2.20(9xH, CH.sub.2CH)                                           a        2.10(3H, CH.sub.3)                                                   k        3.00(9H, OCH.sub.3)                                                  c        3.10-3.40(6H, CH.sub.2)                                              d        3.00-4.00(6H, CH.sub.2)                                              j        3.70(9xH, OCH.sub.3)                                                 e        3.00-4.00(3H, CH)                                                    b + i    6.25-7.05(12(x + 1) H, aromatic)                         ______________________________________                                    

EXAMPLE 11

A polymer was prepared in the same manner as in Example 10 with theexception of using tri(2-vinyloxy)ethyl 1,3,5-benzenetricarboxylate (thefirst compound in Table 1) instead of the trifunctional alkenyl etherused in Example 10.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was athree-branched star poly(p-methoxystyrene) which was 1.6×10⁴ in Mn and1.06 in Mw/Mn. The Mn value agreed well with the value of 1.5×10⁴ whichwas calculated assuming that one molecule of the adduct formed athree-branched molecule.

The three-branched star poly(p-methoxystyrene) was immersed in a sodiumhydroxide aqueous solution at room temperature for 2 days to hydrolyzethe three ester linkages in the center of the three branches and obtaina branched polymer. When analyzed by GPC, the branched polymer was foundto be 5.0×10³ in Mn and 1.07 in Mw/Mn.

EXAMPLE 12

A polymer was prepared in the same manner as in Example 10 with theexception of using hydrogen chloride in place of hydrogen iodide, andzinc chloride in place of zinc iodide, and effecting the polymerizationat a temperature of 0° C. for 20 minutes.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was athree-branched star poly(p-methoxystyrene) which was 1.4×10⁴ in Mn and1.06 in Mw/Mn. The Mn value agreed well with the value of 1.5×10⁴ whichwas calculated assuming that one molecule of the adduct formed athree-branched molecule.

EXAMPLE 13

A polymer was prepared in the same manner as in Example 10 except thatp-tert-butoxystyrene (0.26 mole/1) was polymerized in place ofp-methoxystyrene (0.38 mole/1) at a temperature of 25° C.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained wasthree-branched star poly(p-tert-butoxystyrene) which was 1.3×10⁴ in Mnand 1.07 in Mw/Mn. The Mn value agreed well with the value of 1.4×10⁴calculated assuming that one molecule of the adduct formed athree-branched molecule.

EXAMPLE 14

p-Methoxystyrene was polymerized in the same manner as in Example 10,and 25 ml (0.26 mole/1) of p-tert-butoxystyrene was thereafter added tothe reaction mixture and further polymerized therewith at an elevatedtemperature of 25° C. Subsequently, methanol (330 mmoles/1) containing asmall amount of ammonia water was added to the reaction system toterminate the polymerization and obtain a mixture containing a polymer.The mixture was washed first with a hydrochloric acid aqueous solution(8 vol. %) and then with water, followed by evaporation for the removalof the solvent, etc. to collect the polymer.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was athree-branched star block copolymer comprising poly(p-methoxystyrene)and poly(p-tert-butoxystyrene), and 3.0×10⁴ in Mn and 1.05 in Mw/Mn.

The Mn value agreed well with the value of 2.9×10⁴ which was calculatedassuming that one molecule of the adduct formed a three-branchedmolecule.

The copolymer was further treated with hydrogen bromide to convertpoly(p-tert-butoxystyrene) on the outer side to poly(p-vinylphenol) andobtain an amphiphatic three-branched star copolymer having hydrophobicgroups internally and hydrophilic groups externally.

EXAMPLE 15

In the same manner as in Example 10 with the exception of usingp-tert-butoxystyrene (0.26 mole/1) instead of p-methoxystyrene (0.38mole/1) at a temperature of 25° C., the p-tert-butoxystyrene waspolymerized. Subsequently, 25 ml (0.38 mole/1) of p-methoxystyrene wasadded to the reaction mixture and further reacted therewith at 25° C.for 20 minutes. Methanol (330 mmoles/1) containing a small amount ofammonia water was thereafter added to the reaction system to terminatethe polymerization and obtain a mixture containing a polymer. Themixture was washed first with a hydrochloric acid aqueous solution (8vol. %) and then with water, followed by evaporation for the removal ofthe solvent, etc. to collect the polymer.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was athree-branched star block copolymer comprisingpoly(p-tert-butoxystyrene) and poly(p-methoxystyrene), and 2.8×10⁴ in Mnand 1.06 in Mw/Mn.

The Mn value agreed well with the value of 2.9×10⁴ which was calculatedassuming that one molecule of the adduct formed a three-branchedmolecule.

The copolymer was further treated with hydrogen bromide to convert thepoly(p-tert-butoxystyrene) in the inside to poly(p-vinylphenol) andobtain an amphiphatic three-branched star copolymer having hydrophilicgroups internally and hydrophobic groups externally.

EXAMPLE 16

A 2.0 ml quantity (3.0 moles/1) of isobutyl vinyl ether was dissolved in1.5 ml of n-hexane fully purified and dried in a nitrogen atmosphere,0.5 ml (1.2 moles/1) of 1,4-dioxane was added to the solution, and theresulting solution was maintained at a temperature of 0° C. To thesolution were added first 0.5 ml (1.7 mmoles/1) of the adduct of1,1,4,4-tetrakis[4-(2-vinyloxy)ethoxyphenyl]cyclohexane withtrifluoroacetic acid (CF₃ COOH), as diluted with n-hexane, and then 0.5ml (5.0 mmoles/1) of hexane solution of ethylaluminum dichloride tostart polymerization. After continuing the polymerization at 0° C. for 3hours, methanol (330 mmoles/1) containing a small amount of ammoniawater was added to the reaction system to terminate the polymerization.The reaction mixture was washed first with a hydrochloric acid aqueoussolution (8 vol. %) and then with water, followed by the removal of thecatalyst residue and then by the removal of the solvent, etc. byevaporation to collect a polymer.

The polymer obtained was a four-branched star polyisobutyl vinyl etherwhich was 1.6×10⁵ in Mn and 1.06 in Mw/Mn. The Mn value agreed well withthe value of 1.8×10⁵ which was calculated assuming that one molecule ofthe adduct formed a four-branched molecule. Values obtained by ¹ H-NMRSpectroscopy (270 MHz, CDCl₃)

    ______________________________________                                        (Tetrafunctional vinyl ether)                                                  ##STR47##                                                                    δ(ppm): Peaks                                                                     a         2.25(m, 8H, cyclohexane ring)                                       d         4.00(t, 8H, CH.sub.2)                                               e         4.15(t, 8H, CH.sub.2)                                               g         4.00 and 4.25(dd, 8H, CH.sub.2)                                     f         6.50(dd, 4H, CH)                                                    b         6.80(d, 8H, aromatic)                                               c         7.00(d, 8H, aromatic)                                     (Tetrafunctional initiator)                                                    ##STR48##                                                                    δ(ppm): Peaks                                                                     g         1.50(s, 12H, CH.sub.3)                                              a         2.25(m, 8H, cyclohexane ring)                                       d + e     4.00(m, 16H, CH.sub.2)                                              f         6.15(q, 4H, CH)                                                     b         6.70(d, 8H, aromatic)                                               c         6.90(d, 8H, aromatic)                                     (Four-branched polyvinyl ether)                                                ##STR49##                                                                    δ(ppm): Peaks                                                                     k         0.90(24×H, CH.sub.3)                                          f         1.20(12H, CH.sub.3)                                                 g + j     1.40-2.00(12×H, CH.sub.2)                                     a         2.10-2.40(8H, cyclohexane ring)                                     d,e,h,i,n 3.00-4.00                                                           c         4.10(8H, CH.sub.2)                                                  m         4.65(4H, CH)                                                        b         6.75-7.00(16H, aromatic)                                  ______________________________________                                    

EXAMPLE 17

A 1.0 ml quantity (1.5 moles/1) of isobutyl ether was dissolved in 2.5ml of n-hexane fully purified and dried in a nitrogen atmosphere. Withaddition of 0.5 ml (1.2 moles/1) of 1,4-dioxane, the solution wasmaintained at a temperature of 0° C. To the solution were added first0.5 ml (3.5 mmoles/1) of the adduct of 1,1,4,4-tetrakis4-(2-propenyloxy)ethoxyphenyl]cyclohexane with trifluoroacetic acid, as diluted withn-hexane, and then 0.5 ml (10 mmoles/1) of hexane solution ofethylaluminum dichloride to initiate polymerization. The same procedureas in Example 16 was thereafter followed to obtain a polymer.

The above process afforded a four -branched star polyisobutyl vinylether which was 3.7×10⁴ in Mn and 1.08 in Mw/Mn. The Mn value was ingood agreement with the value of 3.9×10⁴ which was calculated assumingthat one molecule of the adduct formed a four branched molecule.

EXAMPLE 18

A 1.0 ml quantity (0.38 mole/1) of toluene solution of methyl vinylether was added to 2.50 ml of toluene fully purified and dried in anitrogen atmosphere. To the solution was then added 0.5 ml (1.2 moles/1)of 1,4-dioxane. Further added to the solution were 0.5 ml (3.5 mmoles/1)of the same adduct as used in Example 16 and 0.5 ml (10 mmoles/1) ofhexane solution of ethylaluminum dichloride to initiate polymerizationat -15° C. The polymerization was continued for 3 hours, followed by thesame procedure as in Example 16 to obtain a polymer.

Consequently, a hydrophilic four -branched star polymethyl vinyl etherwas prepared which was 6.6×10³ in Mn and 1.06 in Mw/Mn. The Mn valueagreed well with the value of 6.9×10³ which was calculated assuming thatone molecule of the adduct formed a four-branched molecule.

EXAMPLE 19

A polymer was prepared by the same procedure as in Example 16 exceptthat the polymerization was conducted at a temperature of 60° C. for 10minutes.

The polymer obtained was a four -branched star polyisobutyl vinyl etherwhich was 1.6×10⁵ in Mn and 1.10 in Mw/Mn. The Mn value agreed well withthe value of 1.8×10⁵ which was calculated assuming that one molecule ofthe adduct formed a four -branched molecule.

EXAMPLE 20

A 0.25 ml quantity (0.35 mole/1) of isobutyl vinyl ether was dissolvedin 3.25 ml of n-hexane fully purified and dried in a nitrogenatmosphere. A 0.5 ml quantity (1.2 moles/1) of 1,4-dioxane was added tothe solution. Further added to the solution were 0.5 ml (3.5 moles/1) ofthe same adduct as used in Example 16 and 0.5 ml (10 mmoles/1) of hexanesolution of ethylaluminum dichloride to initiate polymerization at 0° C.Three minutes after the start of the reaction, 0.25 ml (0.38 mole/1) of2-vinyloxyethyl acetate was added to the mixture, followed by furtherpolymerization at a temperature of 40° C. for 3 hours. The sameprocedure as in Example 16 was thereafter repeated to obtain a polymer.

The polymer was a four -branched star block copolymer which was 2.6×10⁴in Mn and 1.06 in Mw/Mn. The Mn value agreed well with the value of2.6×10⁴ which was calculated assuming that one molecule of the adductformed a four -branched molecule.

The polymer was further hydrolyzed with an alkali to convert thepoly-2-acetoxyethyl vinyl ether on the outer side to poly-2-hydroxyethylvinyl ether and obtain an amphiphatic four -branched star polymer havinghydrophobic groups internally and hydrophilic groups externally.

EXAMPLE 21

The procedure of Example 20was repeated with the exception of using 0.25ml (0.38 mole/1) of 2-vinyloxyethyl acetate first in place of isobutylvinyl ether to effect polymerization at 40° C. for 2 hours, followed byaddition of 0.25 ml (0.38 mole/1) of isobutyl vinyl ether to effectfurther polymerization at 40° C. for 1 hour.

As a result, a four -branched star block copolymer was obtained whichwas 2.4×10⁴ in Mn and 1.10 in Mw/Mn. The Mn value agreed well with thevalue of 2.6×10⁴ which was calculated assuming that one molecule of theadduct formed a four -branched molecule.

The polymer was further hydrolyzed with an alkali to convert thepoly-2-acetoxyethyl vinyl ether on the inner side to poly-2-hydroxyethylvinyl ether and prepare an amphiphatic four -branched star polymerhaving hydrophilic groups internally and hydrophobic groups externally.

EXAMPLE 22

A 0.5 ml quantity (0.76 mole/1) of isobutyl vinyl ether was dissolved in3.5 ml of toluene fully purified and dried in a nitrogen atmosphere, andthe solution was maintained at a temperature of -15° C. To the solutionwere added first 0.5 ml (3.0 mmoles/1) of the adduct of1,1,4,4-tetrakis[4-(2-vinyloxy)ethoxyphenyl] cyclohexane with hydrogeniodide, as diluted with toluene, and then an ethereal solution (0.2mmole/1) of zinc iodide (ZnI₂) to effect polymerization at -15° C. for 1hour. Methanol (300 mmoles/1) containing a small amount of ammonia wasthen added to the reaction system to terminate the polymerization. Thereaction mixture was washed with a sodium thiosulfate aqueous solution(8 vol. %) first then with water, followed by the removal of thecatalyst residue and thereafter by the removal of the solvent, etc. byevaporation to obtain a product.

The product obtained was a four-branched star polyisobutyl vinyl etherwhich was 2.4×10⁴ in Mn and 1.06 in Mw/Mn. The Mn value agreed well withthe valuce of 2.6×10⁴ which was calculated assuming that one molecule ofthe adduct formed a four -branched molecule.

EXAMPLE 23

The same procedure as in Example 22 was repeated with the exception ofusing the adduct (3.0 mmoles/1) of1,1,4,4-tetrakis[4-(2-propenyloxy)ethoxyphenyl]cyclohexane with hydrogeniodide, as diluted with toluene, in place of the adduct used in Example22 Consequently, a four-branched star polyisobutyl vinyl ether wasobtained which was 2.8×10⁴ in Mn and 1.07 in Mw/Mn.

EXAMPLE 24

A 0.25 ml quantity (0.38 mole/1) of 2-vinyloxyethyl ethyl acetate wasdissolved in 3.0 ml of toluene fully purified and dried in a nitrogenatmosphere, and the solution was maintained at a temperature of -15° C.To the solution were added first 0.5 ml (3.0 mmoles/1) of the sameadduct as used in Example 22 and then a toluene solution (9.0 mmoles/1)of iodine (I₂) to start polymerization. After continuing thepolymerization at -15° C. for 1 hour, the same procedure as in Example22 was repeated to prepare a polymer.

The polymer obtained was a four -branched star poly-2-acetoxyethy vinylether which was 1.6×10⁴ in Mn and 1.06 in Mw/Mn. The Mn value agreedwell with the value of 1.7×10⁴ which was calculated assuming that onemolecule of the adduct formed a four-branched molecule.

EXAMPLE 25

A 0.25 ml quantity (0.38 mole/1) of p-methoxystyrene was dissolved in3.75 ml of toluene fully purified and dried in a nitrogen atmosphere,and the solution was maintained at a temperature of -78° C. To thesolution were added first 0.5 ml (3.3 mmoles/1) of the adduct of1,1,4,4-tetrakis[4-(2-vinyloxy)ethoxyphenyl]cyclohexane with hydrogeniodide, as diluted with toluene, and then 0.5 ml (3.3 mmoles/1) ofethereal solution of zinc iodide. The resulting solution was allowed tostand at -78° C. for 20 hours and thereafter heated to -15° C. to startpolymerization. After continuing the polymerization at -15° C. for 2hours, methanol (330 mmoles/1) containing a small amount of ammoniawater was added to the reaction system to terminate the polymerizationand obtain a mixture containing a polymer. The mixture was washed firstwith sodiumith sulfate aqueous solution (8 vol. and then with water, andthe solvent, etc. were evaporated off the mixture to collect thepolymer.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was afour-branched star poly(p-methoxystyrene) which was 1.5×10⁴ in Mn and1.05 in Mw/Mn. The Mn value agreed well with the value of 1.5×10⁴ whichwas calculated assuming that one molecule of the adduct formed a four-branched molecule. Values Obtained by ¹ H-NMR Spectroscopy (270 MHz,CDCl₃)

    ______________________________________                                         ##STR50##                                                                

    ______________________________________                                        δ(ppm): Peaks                                                                      f       0.90(12H, CH.sub.3)                                                   g + h   1.20- 2.20(12×H, CH.sub.2 CH)                                   a       2.10- 2.40(8H, cyclohexane ring)                                      k       3.00(12H, OCH.sub.3)                                                  c       3.10-3.40(8H, CH.sub.2)                                               d       3.00-4.00(8H, CH.sub.2)                                               j       3.70(12×H, OCH.sub.3)                                           e       3.00 4.00(4H, CH)                                                     b + i   6.25-7.05(16(x+1)H, aromatic)                              ______________________________________                                    

EXAMPLE 26

A polymer was prepared in the same manner as in Example 10 with theexception of using 1,1,3,3-tetrakis[4-(2-vinyloxy)ethoxyphenyl]cyclohexane instead of the trifunctionalalkenyl ether used in Example 25.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was afour-branched star poly(p-methoxystyrene) which was 1.4×10⁴ in Mn and1.09 in Mw/Mn. The Mn value agreed well with the value of 1.5×10⁴ whichwas calculated assuming that one molecule of the adduct formed a four-branched molecule.

EXAMPLE 27

A polymer was prepared in the same manner as in Example 25 with theexception of using hydrogen chloride in place of hydrogen iodide, andzinc chloride in place of zinc iodide, and effecting the polymerizationat a temperature of 0° C. for 20 minutes.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was afour-branched star poly(p-methoxystyrene) which was 1.4×10⁴ in Mn and1.05 in Mw/Mn. The Mn value agreed well with the value of 1.5×10⁴ whichwas calculated assuming that one molecule of the adduct formed afour-branched molecule.

EXAMPLE 28

A polymer was prepared in the same manner as in Example 25 except thatp-tert-butyxystyrene (0.26 mole/1) was polymerized in place ofp-methoxystyrene (0.38 mole/1) at a temperature of 25° C.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained wasfour-branched star poly(p-tert-butoxystyrene) which was 1.4×10⁴ in Mnand 1.06 in Mw/Mn. The Mn value agreed well with the value of 1.4×10⁴calculated assuming that one molecule of the adduct formed afour-branched molecule.

EXAMPLE 29

p-Methoxystyrene was polymerized in the same manner as in Example 25 and25 ml (0.26 mole/1) of p-tert-butoxystyrene was thereafter added to thereaction mixture and further polymerized therewith at an elevatedtemperature of 25° C. Subsequently, methanol (330 mmoles/l) containing asmall amount of ammonia water was added to the reaction system toterminate the polymerization and obtain a mixture containing a polymer.The mixture was washed first with a hydrochloric acid aqueous solution(8 vol. %) and then with water, followed by evaporation for the removalof the solvent, etc. to collect the polymer.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was afour -branched star block copolymer comprising poly(p-methoxystyrene)and poly(p-tert-butoxystyrene), and 2.8×10⁴ in Mn and 1.05 in Mw/Mn.

The Mn value agreed well with the value of 2.9×10⁴ which was calculatedassuming that one molecule of the adduct formed a four -branchedmolecule.

The copolymer was further treated with hydrogen bromide to convertpoly(p-tert-butoxystyrene) on the outer side to poly(p-vinylphenol) andobtain an amphiphatic four -branched star copolymer having hydrophobicgroups internally and hydrophilic groups externally.

EXAMPLE 30

In the same manner as in Example 25 with the exception of usingp-tert-butoxystyrene (0.26 mole/1) instead of p-methoxystyrene (0.38mole/1) at a temperature of 25° C., the p-tert-butoxystyrene waspolymerized. Subsequently, 25 ml (0.38 mole/1) of p-methoxystyrene wasadded to the reaction mixture and further reacted therewith at 25° C.for 20 minutes. Methanol (330 mmoles/1) containing a small amount ofammonia water was thereafter added to the reaction system to terminatethe polymerization and obtain a mixture containing a polymer. Themixture was washed first with a hydrochloric acid aqueous solution (8vol. %) and then with water, followed by evaporation for the removal ofthe solvent, etc. to collect the polymer.

GPC and ¹ H-NMR spectroscopy revealed that the polymer obtained was afour-branched star block copolymer comprising poly(p-tert-butoxystyrene)and poly(p-methoxystyrene), and 3.0×10⁴ in Mn and 1.08 in Mw/Mn.

The Mn value agreed well with the value of 2.9×10⁴ which was calculatedassuming that one molecule of the adduct formed a four-branchedmolecule.

The copolymer was further treated with hydrogen bromide to convert thepoly(p-tert-butoxystyrene) in the inside to poly(p-vinylphenol) andobtain an amphiphatic four -branched star copolymer having hydrophilicgroups internally and hydrophobic groups externally.

What is claimed is:
 1. A process for preparing a three-branched orfour-branched star compound characterized by polymerizing an olefincompound represented by the formula ##STR51## wherein A is a single bondor phenylene group, and R³ is a hydrogen atom or methyl group and R⁴ isa monovalent organic group when A is a single bond, or R³ is a hydrogenatom and R⁴ is an alkyl group when A is a phenylene group, using theadduct of a polyfunctional alkenyl ether represented by the formula

    R.sup.2 --O--CH═CHR.sup.1).sub.n                       (I)

wherein R¹ is a hydrogen atom or methyl group, n is an integer of 3 or4, and R² is a trivalent organic group when n is 3 or a tetravalentorganic group when n is 4 with a cation-donating compound to prepare athree-branched or four-branched star compound represented by the formula##STR52## wherein x is 1 to 10,000, Z is a terminator residue, and R¹,R², R³, R⁴, A and n are as defined above.
 2. A process as defined inclaim 1 wherein an alkenyl ether represented by the formula ##STR53##wherein R³ is a hydrogen atom or methyl group, and R⁴ is a monovalentorganic group is polymerized using the adduct of a trifunctional alkenylether represented by the formula ##STR54## wherein R¹ is a hydrogen atomor methyl group, and R² is a trivalent organic group with acation-donating compound to prepare a three-branched star alkenyl etherrepresented by the formula ##STR55## wherein x is 1 to 10,000, Z is aterminator residue, and R¹, R², R³ and R⁴ are as defined above.
 3. Aprocess as defined in claim 1 wherein an alkyloxystyrene represented bythe formula ##STR56## wherein A is a phenylene group, and R⁴ is an alkylgroup is polymerized using the adduct of a trifunctional alkenyl etherrepresented by the formula ##STR57## wherein R¹ is a hydrogen atom, andR² is a trivalent organic group with a cation-donating compound and abivalent metal halide as an activating agent to prepare a three-branchedstar alkyloxystyrene represented by the formula ##STR58## wherein x is 1to 10,000, Z is a terminator residue, and R¹, R², R⁴ and A are asdefined above.
 4. A process as defined in claim 1 wherein an alkenylether represented by the formula ##STR59## wherein R³ is a hydrogen atomor methyl group, and R⁴ is a monovalent organic group is polymerizedusing the adduct of a tetrafunctional alkenyl ether represented by theformula ##STR60## wherein R¹ is a hydrogen atom or methyl group, and R²is a tetravalent organic group with a cation-donating compound toprepare a four-branched star alkenyl ether represented by the formula##STR61## wherein x is 1 to 10,000, Z is a terminator residue, and R¹,R², R³ and R⁴ are as defined above.
 5. A process as defined in claim 1wherein an alkyloxystyrene represented by the formula ##STR62## whereinA is a phenylene group, and R⁴ is an alkyl group is polymerized usingthe adduct of a tetrafunctional alkenyl ether represented by the formula##STR63## wherein R¹ is a hydrogen atom or methyl group, and R² is atetravalent organic group with a cation-donating compound, and abivalent metal halide as an activating agent to prepare a four-branchedstar alkyloxystyrene represented by the formula ##STR64## wherein x is 1to 10,000, Z is a terminator residue, and R¹, R², R⁴ and A are asdefined above.
 6. A process as defined in claim 2 or 4 wherein thepolymerization is effected in the presence a Lewis acid.
 7. A process asdefined in claim 2 or 4 wherein the polymerization is effected in thepresence of a Lewis acid and an organoaluminum compound.
 8. A process asdefined in any one of claims 1 to 5 wherein the adduct is a compoundrepresented by the formula

    R.sup.2 --O--CHB--CH.sub.2 R.sup.1).sub.n                  (IV)

wherein R¹, R² and n are as defined in claim 1, and B is the portion ofthe cation-donating compound remaining after the donation of cation. 9.A process as defined in any one of claims 1 to 5 wherein a plurality ofdifferent olefin compounds (I) are reacted successively to obtain amulti-branched star polymer in the form of a block copolymer.
 10. Aprocess as defined in any one of claims 1 to 5 wherein x is 4 to 5000.